The maker of one of the most popular antiviruses available for Windows – Kaspersky Lab – has accused Microsoft of anticompetitive practices, by bundling Windows Defender with Windows.

The founder of Kaspersky Lab and Russian billionaire developer, Eugene Kaspersky, has filed complaints against Microsoft’s anticompetitive practices in the EU and Russia. In a blog post – aptly titled “That’s It. I’ve Had Enough!” – he explains his frustrations with Microsoft.

Though Windows Defender has been around since the era of Windows 7 – Microsoft only started bundling it with Windows 8 and continued to do so with Windows 10. Kaspersky, in his blog post, is very particular about his qualms with how Windows 10 behaves in regards to 3rd-party anti-virus software.

It is highly recommended that you read Kaspersky’s own blog post – it’s incredibly well written, and he gives a full explanation for his anger. However, here’s the summary of a few points he mentions:

Windows 10 has been receiving frequent updates – great for the users. However, the upgrade process uninstalls every anti-virus software present, despite users choosing to keep personal files and apps.

3rd party developers are given six days to check their software for compatibility before the release of an upgrade – this used to be a two-month period, before Windows 10.

If a 3rd party anti-virus software is installed on a Windows 10 device, Defender still shows an alarming interface with a big “juicy” turn on button, compelling the user to activate Defender… and disabled the 3rd party anti-virus.

If a 3rd party anti-virus product license expires, Windows will show a warning for three days – if the user does nothing, Windows will switch them to Defender by itself.

Windows 10 introduced a limit for how many anti-virus programs a device can have installed – the limit is two; while that sounds reasonable, if a user is using a 3rd party anti-virus and then installs a 2nd one as a trial to test out, but forgets to delete or purchase the 2nd anti-virus after the trial expires – Windows will quietly disable both 3rd-party anti-virus programs, and enable Defender.

These five points are the major issues Kaspersky has with Microsoft – but they are not the only ones; Kaspersky also quotes a Microsoft video, where Chris Hallum – Senior Product Manager at Microsoft for Windows Client Security asks viewers to consider “kicking out 3rd party anti-virus clients.”

The Russian Probe

While Kaspersky has filed complaints to both the EU and Russian authorities, Russia’s Federal Antimonopoly Service has already started investigating Microsoft’s anti-competitive practices.

Anatoly Golomolzin, Deputy Head of FAS, says “due to the fact that Microsoft itself is a developer of antivirus software Windows Defender, which automatically launches if the third-party software had no time to adapt to Windows 10, this decision results in unjustified advantages for Microsoft on the software market.”

The Concerns

Kaspersky’s concerns are certainly not unfounded – any Windows 10 user can see all of the things he points out. In fact, Windows 10’s tendency to shove its preference on top of users has been a cause of concern for a while.

Whether adequate response comes out of Kaspersky’s complaints is yet to be seen – EU doesn’t have very friendly relations with Russia at the moment, and Kaspersky Lab is as Russian as it gets. The Russian authorities, however, have already started an investigation.